Linkage.



).MBECKERI INK-AGE.. APPLICATION FILED-MAR. I3. 19-15.

'- Patent@ July 4.-, 1916.

@QQ I i UNITED STATES- PATENT OFFICE.-

JOSEPH- BECKER, OF WSHINGTON, DISTRICT OF. COLUMBIA.. i

LINKAGE Specification of Letters Patent.

IPa touted July 4,191.6.

Original application led June 17, 1913, Serial No. 774,220. Divided mlthis application led March 13,

1915. seriaiNo. 14,178.

T o all whom t may concern.'

Be it known that l, JOSEPH BECKER, a

citizen of the United States, residing vat i Washington, in the District'of Columbia,

' lowing is a' specification.

' being drawn to the separably patentable have invented certain new and useful lm provements 1n Linkages, of whlch the fol- The present application identified for convenience of cross reference as Case `Adds a.

division of my prior application, Case Aa,

lthe simpler form of Fig. 2.

In Fig. 1,v and as more clearly seen in Fig. 2, a constant product is formed by any two now Patent 1,136,761, issued April 20, 1915,

constant product linkage of such Case Aa.

My invention, therefore, consists 'generally in the pantographic combination of two unequal but similar `Peaucelliercells and it consists. specifically in a specially useful 'and greatly simplified form of such combination. y

In the accompanying drawings:l Figure-1 Hshows the invention in its most general form,

as it must be made tov meet all `possible uses contemplated in my Casella. Fig. 2 shows the invention in `asimplerform, ,also useful in Case Aa, but having other useful appli'cations.l Fig. 3 shows a still further simplification of Fig. ,2. Figs, 4, 5 and Gareexplanatory diagrams'.

' links CD and CF; and this articulatedicom- As 'well understood, the Peaucellierccell consists in an articulated rhombusDFFG, Fig. 4, having diagonally opposite )ointsD- and F connected by two articulated equal bination orf-.cellf as it is called, determines two alined co-varying space .elements CG 'and CE that form a constant product mounting, on such large Peaucellier cell of CDEFG in which all dimensions are and;

remain parallel 'to the lcorresponding dimensions of the larger-cell; such similarity bef ing maintained by' provlding pantographic parallelogram connections, such as WV and I v*referred to as the poles, and the ilnterpolarl distance CC', is a constant fraction, i1 in Fig. 1, of the distanceCE, a result which depends -onthe pantogra-phic connection and which is of considerable importance in my 'Case Aa, where the ratio CC/ must `have a definite value. .It must, for instance, be equal to Zero when the. lenses A- and B to be used have focal lengths ythatare numerically equal, and, in this case= Fig.1 assumes There only -two of such, spaceelements i are required, as in most. uses', the other two and 4theirlinks'ma-y be suppressed. Thus .by suppressing CG and CE in Fig. .2 we

form the consta-nt product linkage of Fig.

f 3', and by suppressing CGry and @Ein- Fig. 2 we form the constant. product/linkage. of

Fig. 6,"whichfis a'mere reversal of Fig. '3, and is added 'mainly to lshow that there is no substantial difference betweenmy linkage and that ofthe Dutert foreign patents,

lwhich are fully-cited in Note?) below.

Structural proportions-If the constant ratio of a dimension such as vDE inthe large Peaucellier cell, Figs. 1 and 2, to the 'corre-Y sponding-dimension -DE in the small cell be designated by R, then all dimensions irlvolved may conveniently be defi-ned as in According to the established -Peau'cellier practice, we have the .small 'ce-ll, Fig. 5,

which is our first andsmallest constant A product. With this equation'l Aand the aid .of the'above'table the three other products may be written out almost directly as follows:

OG :m

Product four CG.CE:(m2-a2)ft2 Product one,` relating to the small Peaucellier cell, Fig. 5, and product four, vrelating to the largeljeaucellier cell, Fig. Ll,

are well known and need no further eXf pla-nation.v Product two, relating to Fig. 3, and product three, relating to Fig. .6, are

equal. IThese equal products, product two and product three, contain three different structural constants m,.a and R, any two of which maybe selected arbitrarily when a certain desired constant product is tol be Yobtained.

y :a and 1/ -.are shown throughout all views as is pushed over closer to G. Kempe in his a: equal to '25 centimeters and g/ equal to 1G centimeters.

NOTE 1.,-In linkage literature the Peaucellier constant product linkage CDEFG, Fig. 4, is often referred to as consisting of a kite7 CDFG combined with a spear head CDFE; the terms being reversed .when C book H ow to Draw a Straight Line; a Lec`- are 0a Linkages; London, 1877, uses these terms. My Fig. 3, therefore,may be considered as composed by uniting the kite CDFGr of the small Feaucellier cell with Athe spear head CDFE of the large Peau-v cellier cell; and my Fig. G, which is simply the linkage of Fig. 3 reversed and shown in a different position, may similarly be considered as composed by uniting the kite CDFG of the large Feaucellier cell to the spear head CDFE of the small Peaucellier celL niemals In such old Phillips' linkage, however, the kite and spear head are 'united by connecting the sides of theirv equal angles; whereas, my linkage is formed by connecting the sides of the angles which'are opposed to such equal angles, andwhich unite to form four right angles. v

'NOTE 3..-1 am aware .that .Kempo in Fig.

' 10, page 17,of his book (flow to Draw a.

.Straight Lzfn'e; a'llaatmjeoa Linkages; London, 1877). y'shows a later French type of Peaucellier cell consisting of a large kite and'a small spear-head, somewhatas in my Fig. 6; butl this later French linkage has itslever elements crossed and fulcrumed at the third termina-l as polar point of the linkage; whereas, the levers of my Fig. G, are not 'crossed7 and `are fulcrumed at the second terminal as polarv point.

NOTE str-I am aware that t-he combination of a Feaucellier cell element with the corresponding cellelement made larger, is old'in the American ./lactz'a-ist, New York, 1391, yol. 14, lin three seyeral places as follows First, old in Fig. 16, page 4, of the October 29v number, where a small spear-head ADCF is combined with a'large kite AGH to vdetermine the cowarying factors AC and AH of the constant product AGAH; ysecondly old,I in Fig. 18; page 4, of the 4same October Q9 number, where a small kite ADCF is com-v binedwith a larger' spear-head EIHG to determine the cio-varying factors AC and rAH of the constant product AGH; thirdl-y,'old, in Fig-19, page 11, ofthe December 3 number,vwhere -a large kite, AJKI, is combined with a smalls1 ear-h'ead,-AGCH, to determine the co-varying factors AC and AK of the constant product AGAK; but, in each of these three different linkagesthe polar terminal being at is not the second one of the three terminals as in my Fig. 6.

`Nora 5.41 am aware that each of the three American Machinist lihkagesl referred to in Note 4, really consists of a-complete seven bar Peaucellier straight line linkage pantographically combined with an eXtra large Peaucellfier cell element, which cell element is formed mainly by the addition of two links forming: an eXtra large Akite AGHI in Fig.

rio

16;'a'n extra large spear-head Fll'ltl in Fig.

18; and an eXtra large kite AJKI in Fig. 19; but not one of these three linkages shows two complete and unequallylarge Peaucellier cells comprising two kites and two spearheads as in my Fig. 1 or in my Fig. Q.

NOTE 6.-1 am aware that hars CD, DE-

of Fig. 2, and my still simpler form of Fig.

8, Were all three invented prior to the said earliest claimed Dutert date of June 17, 1911.

'lvhat I claim as my invention and desire to secure by Letters Patent` is:

- 1. A; constant productl linkage comprising a large Peaucellier cell and a similar smaller Peaucellier cell, and connections to keep their corresponding angles equal.

2. A linkage adapted to determine consta-nt product spacel elements between three terminalsguided to move in the same straight path, such linkage comprising a link ivith one end pivoted to the iirst terminal, a longer link with one end pivotedto the third terminal and a straight lever having one end fulcrumed on the second terminal, said lever having its longer lever arm connectedy with the longer of the said two links and its shorter' lever arm connected with the shorter of the said tivo links.

3. A linkageadapted to determine constant product space elements between three terminals guided to move in the same straight path, such linkage comprising a link with one end pivoted to the iirst terminal, a longer link vvith one end pivoted to the third terminal and a straight lever having one end fulcrumed to the second terminal, said lever having its longer lever arm connected with the longer of the sai-d -tivo links and its shorter lever arm connected with the shorter oi the said tivo links; said tvvo links and said tivo lever arms being of such lengths as to form a link ratio that is equal to the corresponding lever arm ratio.

In testimony7 whereof, I have signed my naine to this specification in the presence ot tivo subscribing witnesses.

JOSEPH BECKER.

Witnesses MARY E. CoivELL, H. P. HOWARD, Jr. 

